Remote control switching apparatus



M. R. JOHNSON REMOTE CONTROL SWITCHING APPARATUS June 24, 1941;.

Filed Jan. 4, 1939 Inventor: Marwin R.Johnson Patented June 24, 1941 STAES ll iarwin R. Johnson, Scotia,

N. Y., assignor to General Electric Company, a corporation of New York Application January 4, 1939, Serial No. 249,350

5 Claims.

My invention relates to switching apparatus and more particularly to remote control switching apparatus for selectively connecting a plurality of prearranged electric circuits to an electric apparatus.

The invention is applicable particularly for use in connection with aircraft high frequency apparatus such as short-wave transmitters although the invention is not limited to this use.

In connection with aircraft radio apparatus it i has been suggested heretofore to control the operation of the apparatus from the pilots position. In such aircraft remote-control apparatus a plurality of preset circuits providing predetermined frequency channels are arranged to be available l for selection by the pilot. It is the principal object of the present invention to provide a novel and improved remote control switching means for such apparatus.

It is a particular object of the invention to provide, in a switching apparatus for aircraft radio or other uses and which is of the type wherein a shaft or other switch member adapted for longitudinal movement carries thereon contact members rotating thereabout and moving longitudinally therewith and cooperating with fixed contacts, novel and improved means for actuating the rotatable and longitudinally movable shaft or switch member for selecting the desired channels.

In accordance with the present invention the movable contacts, which are preferably mounted rigidly on the shaft and are rotated thereby, are adapted to be moved to the desired positions positively and rapidly by means including a step-bystep mechanism. In operating the shaft, or contact carrying member, to change from one channel to another the initiation of the rotation of this member is positively prevented until the member has been moved longitudinally, or translated, sufficiently to disengage the movable contacts from the fixed contacts corresponding thereto. A delayed action relay means is provided cooperating with the shaft rotating means to insure positive and complete operation of the latter means at each step of the rotation of the shaft. Stop means cooperating with the shaftrotating means at each step of the rotation of the shaft are provided further to insure positive action of the rotating means. A means is provided cooperating with the means for translating, or moving longitudinally, the movable contact carrying shaft or member, to prevent undesirable current drain due to the shaft translating means.

The novel features which are considered to be characteristic of my invention are set forth with particularity in the appended claims. My invention itself, however, both as to its organization and method of operation together with further objects and advantages thereof may best be understood by reference to the following description taken in connection with the accompanying drawing the single figure of which illustrates schematically an embodiment of my invention.

In the drawing the circuits of the remote controlled apparatus (not shown) which are to be selected from the operators position are connected to switches designated generally by S1, S2, and S3 comprising fixed contact plates ill, I! and I2, banks of fixed contacts i3, i l and Hi and movable bridge members 16, if and it which are mounted insulatingly and rigidly on a shaft l9 and which support contacts 20, El and 22 adapted to engage the fixed contacts i3, i4 and i5, and contacts 23, 24 and 25 adapted to engage the contact plates. In the present embodiment of the invention only three switches S1, S2 and S3 are shown and these swtiches are illustrated as capable of being arranged in four different positions for selecting four frequency channels. The invention, however, is not limited as to the number of such switches and as to the number of positions for selecting channels. As the circuits to be remotely controlled form no part of my present invention they will not be described further herein.

In selecting desired channels by the remote control switch means illustrated in the drawing it is necessary that the shaft i 9 be translated longitudinally, then rotated to a selected angular position, and finally translated longitudinally in the opposite direction from the first translation. To effect the longitudinal motion a spring element 26 is arranged adjacent one end of the shaft to bias the shaft in the first direction, which is toward the left in the drawing, and a translator element 27 comprising a solenoid 28 and a plunger 29 is arranged to move the shaft in the second direction, which is toward the right in the drawing, against the pressure of the spring 26 through a lever 3i? bearing against the other end of the shaft. To maintain the shaft in its right hand position against the pressure of the spring 26, a latch member 3! is provided which is normally biased by a spring 32 toward the lever 38 and which is adapted to move into looking position behind the end 33 of the lever 39 when the shaft 59 is moved to its right hand position. To permit the shaft to be released for movement to its left hand position after being locked into its right hand position by the latch 3|, a latch trip relay 34 is provided comprising a trip coil 35 and an armature 36 which is preferably formed integrally with the latch member 3i. To prevent undesired current drain through the translator solenoid 28, a pair of interlock or isolating contacts 3'! are provided, in series with the solenoid 28, which are arranged to be held open by the latch 35 when the shaft is in its right hand position, thereby to deenergize the translator Zl during the latched-in periods.

To rotate the shaft it after being moved by spring 26 to its released position, which is its left hand position in the drawing, a ratchet wheel 38 is mounted to rotate integrally with shaft I9. Preferably ratchet wheel 38 is mounted on a stub shaft 39 which is of smaller diameter than the latter shaft l9, rigidly connected thereto and forming an extension thereof, the stub shaft being journaled in a frame or support member lfl.

To cause spring 25 to exert a biasing pressure on; shaft l9 when the shaft is moved to its latched-in or right hand position, the spring is mounted, on stub shaft 39, between a thrust washer ii abutting the right-hand end of shaft [9 and a thrust plate or member Q2 through which the stub shaft is slidable and which is connected by studs or rods 33, passing through corresponding openings M in ratchet wheel 38, to a thrust member or plate abutting the support member ii! and through which the stub shaft 39 is slidable. To rotate the ratchet wheel 38, a ratchet motor device indicated generally by the numeral 56 is provided comprising a magnet 4'! having a coil to and an armature 49 pivoted thereon which is connectedto a pawl member 50 and which is adapted to move the pawl against the tension of a pawl spring 5!. The ratchet motor arrangement is such that the pawl 50 is normally biased into contact with ratchet wheel 38' by spring 5!, and is adapted to be drawn back from the wheel, or cocked, against the pressure of the latter spring, by the pull of the magnet ll. To energize and deenergize alternately the magn-et coil as of the ratchet motor 45, arelay means 52 is provided having its contacts 53 in circuit with magnet coil 58, and its operating coil 54 in series with apair of ratchet motor impulse contacts 55 arranged to be opened by the pawl 50 when the latter is drawn back from the ratchet wheel 33 by the magnet al.

In order to maintain the magnet coil G8 energizedthrough the full travel of the armature 39 the relay 52 is so arranged, by any suitable means (not shown) that the contacts 53 thereof are slow opening to a predetermined degree. A detent 56 is mounted in contact with the ratchet wheel. 38 to prevent reverse rotation of the wheel. To insure that the ratchet motor 36 will not be energized to cause rotation of shaft i9 unless the shaft istoward its left hand position at least far enough to cause the movable contacts of switches S1, S2 and S3 to be disengaged from the corresponding fixed contacts and contact plates, a pair of ratchet motor interlock contacts 51 in circuit with actuating coil 55 of relay 52 are provided adapted to be actuated by the lever so.

Eccentric adjustable stop means 58 and 59 are provided to position the pawl 58 accurately during and after operation of the ratchet motor means Q5. The eccentric stopmeans 53 is so arranged as to limit the motion of the pawl toward the ratchet wheel 38. Eccentric stop means. 59 is so arranged as to maintain the pawl in proper, alignment withthe wheel 38,,and to providea positive means which prevents overrunning of the wheel 38 during rotation thereof by the ratchet motor device, and in cooperation with the spring El maintains the wheel 38, together with the shaft [9 and the switch parts connected thereto, locked in proper position after a channel has been selected by the operator.

For energizing the various actuating coils of the above described system, current is supplied thereto from the circuit 60 having terminals BI and 62 connected to a current source (not shown) of preferably low voltage, for example, fourteen volts. The energizing current is controlled by an auxiliary relay 63 in cooperation with a manually or otherwise operated selector switch means. The relay 63 is preferably mounted upon or closely adjacent to the above described selective switch apparatus, which itself is mounted remote from the operators position. The relay 63 comprises an actuating coil Bil requiring only a relatively small amount of energy, for example one-tenth of an ampere, for its operation, an armature normally in closed position but adapted to be biased to open position by a spring 55 when coil 64 is deenergized, and a bank of contacts 67 adapted to be actuated by the armature 65. One terminal of coil 64 is connected to one terminal as M of circuit 8% and the other terminal of coil Be is connected to the movable arm or contact member 58 of a four point selector switch 89 mounted at the operators position and therefore remote from the switching apparatus. Fixed contact points C1, C2, C3 and C4 of the latter switch are connected respectively, by a cable having wire which need be only very light because of the small amount of current in coil 54, to corresponding fixed contact points C1, C2, C3 and C4 of a switch or commutator ll] comprising a rotating contact or brush member ll mounted on the stub shaft 39 and adapted to be rotated thereby into contact with the latter fixed contacts. The detent 55 is preferably connected to ground.

,The circuit connections for translator element 2i may be traced from supply circuit terminal 6!, through a movable contact 12 and a fixed contact it of switch bank 5?, translator interlock or isolating contacts 31, through solenoid 23, to ground or terminal 82 of the supply circuit. The circuit connections for latch trip relay 3 extend from supply circuit terminal 6!, through movable contact l2 and a fixed contact 14 of switch bank 61, and through trip coil 35 to ground. The circuit connections for the ratchet motor it include two branches; first, the connections for the actuating coil iSof. the ratchet motor, which extend from supply circuit terminal 6!, through contacts 53 ofthe slow operating relay 52, through the coil ditto-ground; second, the connections for the slow operating relay 52, which extend from supply circuit terminal Bl, through a movable contactlE and a fixed contact 16 of switch bank El, through ratchet motor interlock contacts 57, actuating coil Moi relay 52, and ratchet motor impulse contacts 55 to ground. The circuit connections for the actuating coil 64 of the auxiliary relay 63 extend from supply circuit terminal 6|, coil 54, selector switch 69, commutator or switch Til, stub shaft 39, ratchet wheelSS, through detent 5G to ground.

When the parts'o-f the above-described selectiveswitch apparatus are, as shown in the drawing, in normal position for operation of the associated radio or other circuits on a predetermined channel, assuming that energizingcun rent, from the current source 1 is supplied to. circuit 60, all of the actuating coils of the system are in deenergized condition except coil 64 of auxiliary relay 63 the circuit of which is in closed condition through its two switches 69 and 10. Thus in the circuit including coil 23 of translator 27!, contacts 12 and 13 of auxiliary relay 63' are in closed position but translator isolating contacts 3'! are in open position. In the circuit including coil 35 of latch trip relay 34, contacts 72 and M of auxiliary relay 63 are in open position. In the circuit including coil d8 of ratchet motor 46, contacts 53 of slow operating relay 52 are in open position. In the circuit including coil 54 of slow Operating relay 52, contacts 15 and 16 of auxiliary relay 63 and ratchet motor interlock contacts 5'! are in open position, and ratchet motor impulse contacts 55 are in closed position. The shaft l9 being in its right hand position and being locked therein by latch 31, the switches S1, S2 and. S3 are in closed position for operation of the system on the frequency channel corresponding to fixed contact 04 of the selector switch 69, movable contacts 23, 24 and 25 being pressed against the contact plates It, H and I2 and the contacts 20, 2t and 22 being pressed against those contacts of fixed banks it, i l and I5 which correspond to the above channel determined by the selector switch.

In operation of the invention to select a different frequency channel from the channel corresponding to the illustrated position of selector switch 59, for example to select the channel corresponding to the fixed contact Ci of the selector switch, the operator moves the movable contact element 68 away from its illustrated po sition in engagement with contact C4 and into engagement with contact C1. The circuit including actuating coil G l of auxiliary relay 853 is thereby opened and this relay is deenergized, releasing the armature 85 and permitting spring 66 to actuate the movable contacts 72 and F5 to cause contact 72 to be released from contact 13 and to engage contact 14, and to cause contact 15 to engage contact 16. Trip coil of latch trip relay 34 is then energized from supply circuit 6!! through contacts 72 and M and actuates the armature 36 against the tension of spring 32, thereby disengaging latch 3| from the end 33 of lever 33. Translator isolating contacts 31, associated with latch 3i, close when latch trip relay 34 thus operates to release lever 36 but since contacts 12 and 13, in the circuit including coil 28 of translator 27, are at this time open due tothe action of spring 65 of auxiliary relay 63, the translator remains deenergized, therefore permitting the shaft I9 to be moved, by the pressure of spring 26, from its illustrated latched-in or right hand position toward its latch-out or left hand position. Until the shaft has shifted to the left a distance sufiicient to move the contacts 28 and 23, El and 24, and 22 and 25 of switches S1, S2 and So well out of engagement with the fixed contacts and contact plates with which they were previously in engagement the ratchet motor interlock contacts 51 remain open, thereby preventing actuating current from supply circuit 50, and through contacts l5 and 16 of relay 63 and the ratchet motor impulse contacts 55, from energizing the coil 54 of slow operating relay 52 and thus closing contacts 53 in circuit with ratchet motor coil 48 to actuate the ratchet motor. When, however, shaft I9 moves still further to the left, but preferably before it reaches its extreme latch-out or left-hand position, the ratchet motor interlock contacts 5? close, and actuating current is then supplied to relay coil 54 to close contacts 53.

With shaft l9 thus in its left-hand position and the movable elements of the frequency channel switches S1, S2, and S3 out of engagement with the previously engaged fixed elements, coil 48 becomes energized from supply circuit 60 through the contacts 53 and actuates the armature 49 to draw pawl 50 into its set, or cooked position against the tension of spring 5 l. Before the pawl member 50 reaches its set or outer position, it opens the ratchet motor impulse contacts in circuit with coil 54 of relay 52. Contacts 53 of relay 52 therefore tend to open and thereby to deenergize ratchet motor coil 48 and to limit the action of the latter coil in moving pawl 50 to its desired set position. However, relay 52 being so arranged that the opening of contacts 53 is delayed by a predetermined short period of time, therefore the ratchet motor coil 48 continues to be energized until the pawl is moved fully, against spring 5!, to its predetermined set position. At the end of the travel of pawl 50 to its set position, contacts 53 open, the ratchet motor coil 48 is then deenergized, and the pawl is pulled back .by spring 5! to advance the ratchet wheel 33 in the desired direction which in the present instance is counterclockwise looking at wheel 38 from the commutator 16 end of the device. When the pawl 59 has completed its spring-impelled movement into contact with ratchet Wheel 38 to advance the wheel one tooth, the wheel is securely locked against over-running since the point of the pawl forms a wedge between eccentric stop 59 and a tooth of the wheel.

As the pawl moves, by the action of spring 5i to the end of its power stroke, the ratchet motor impulse contacts 55 in circuit with slow operating relay coil 54 reclose. The latter relay is then again energized to close its contacts 53 to energize the ratchet motor 6. The ratchet motor 46 then again operates, in the manner above described, to advance the ratchet wheel 38 another step. The step-by-step process is continued rapidly thereby moving the movable contact member ll of commutator 16 toward the commutator fixed contact Ci.

At the instant the wheel 38 has rotated sufiiciently to cause movable contact 7! to engage fixed contact C1 the actuating coil 64 which is now in circuit with movable member 68 and fixed contact C1 of selector switch 59 and movable mem ber H and corresponding fixed contact C1 of commutator I9, is reenergized thereby retracting armature against the tension of spring 65 and moving movable contact 72 of switch bank 672' out of engagement with fixed contact 74 and into its original illustrated position in engagement with fixed contact l3, and moving movable contact '55 to its original illustrated position out of engagement with fixed contact lit. The circuit including coil 54 of slow operating relay 52 then being opened at contacts it and 75, contacts 53 of relay 52 return to and remain in their normal open position. Ratchet motor coil 48, in circuit with contacts 53, remains deenergized, and ratchet wheel 33 remains locked in the channel position corresponding to fixed contact C1 of the selector switch, with the movable contacts of switches S1, S2, and So opposite the fixed contacts for this channel position. At the same instant, the circuit including latch trip relay coil 35 being reopened at contacts 12 and 14 and the circuit ineluding coil 28 of shaft translator?! being reclosed at contacts 12 and 13, the translator is energized through the latter contacts and isolating contacts 37 to move shaft IQ-back to its right hand position thereby pressing the movable contacts of switches S1, S2, and S3 into engagement with the fixed contacts corresponding to channel 01, and coil 35 of latch trip relay 3% is deenergized thereby permitting spring 32 to set latch 3i into position behind the end 33 of lever 38 .tolock shaft Hi again into its latched-in position. When the latch 35 moves into position to lock the lever 36, the translator isolating contacts are reopened by the latch, thereby preventing, in translator coil 28, flow of energizing current which is not required during the latchedin periods of operation of the system, or operation on the predetermined frequency channels.

To disconnect the remotely controlled apparatus from the frequency channel corresponding to contact C1 and to select one of the remaining channels, corresponding to C2 or C3, or to select again. the channel corresponding to C4, the operator, by setting the movable contact 53 in engagement with that one of the contacts C2, C3, and C4 corresponding to the desired channel, initiates the above-described sequence of operations which is completed without further attention from the operator. The switches S1, S2, and S3 are placed in operative position within a time period of the order of three secondsfor transferring from a given channel, as the C1 channel, to one, as the C4 channel, requiring the maximum rotation of the shaft 53. The time required for selecting a channel, as the C2 channel, closely following the given channel is correspondingly shorter.

My invention has been described herein in a particular embodiment for purposes of illustration. It is to be understood, however, that the invention is susceptible of various changes and modifications and that by the appended claims I intend to cover any such modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. In a switching apparatus including switch means for selecting prearranged circuits comprising a shaft, fixed contacts connected respectively to said circuits and a movable contact cooperating therewith carried by said shaft, an adjustable selector switch and a selector switch in series therewith actuated by said shaft, a current source, a control relay energized from said source through said selector switches when said shaft is in position to engage said movable'contact with one of said fixed contacts thereby to select one of said circuits, means comprising a relay controlled by said first relay to lock said shaft in said position and to release said shaft when said adjustable switch is moved to select another of said circuits, means to move said shaft longitudinally to disengage said movable and fixed contacts, a step by step mechanism comprising a magnet and means controlled by said first relay to energize said magnet periodically until said shaft is rotated to a second position se lected by said adjustable switch, means comprising a switch controlled in accordance with the longitudinal movement of said shaft to prevent said energizing of said magnet until said movable and fixed contacts are fully disengaged, and a translator magnet controlled by said first relay to return .said shaft to locked position.

2. In a switching apparatus including switch means .for selecting prearranged: circuits comprising a shaft, fixed contacts connected respec tively to said circuits and a movable contact 00- operating therewith carried by said shaft, an adjustable selector switch and a selector switch in series therewith actuated by said shaft, a current source, a control relay energized from said source through said selector switches when said shaft is in position to engage said movable contact with one of said fixed contacts, means controlled by said relay to lock said shaft in a selected angular position corresponding to one of said circuits and to release'said shaft upon movement of said adjustable switch to initiate the selection of another of said circuits, a spring means to move said shaft longitudinally, a step by step mechanism comprising a pawl, a spring to actuate said pawl, a magnet to retract said pawl against the pressure of said spring and means controlled by said relay to energize said magnet periodically to cause said pawl to rotate said shaft to a second selected position, means comprising a switch controlled in accordance with the longitudinal movement of said shaft to delay the initiation of said energizing of said magnet, and a translator magnet controlled by said relay to move said shaft longitudinally to engage said movable contact with another of said fixed contacts.

3 In a switching apparatus including switch means for selecting prearranged circuits comprising a shaft, fixed contacts connected respectively to said circuits and a movable contact cooperating therewith carried by said shaft, an adjustable selector switch and a selector switch in series therewith actuated by said shaft, a current source, a control relay energized from said source through said selector switches when said shaft is in position to engage said movable contact with one of said fixed contacts, means comprising a relay controlled by said first relay to lock said shaft in a selected angular position corresponding to one of said circuits and to release said shaft when said adjustable switch is moved to select another of said circuits, a spring means to move said shaft longitudinally, a ratchet mechanism to rotate said shaft comprising a magnet and means controlled by said first relay to energize said magnet periodically until said shaft rotates to a second selected position, a translator magnet controlled by said first relay to move said shaft into locked position, and a switch controlled by said second relay to maintain said translator magnet in deenergized condition while said shaft; is in said locked position.

at. In a switching apparatus including switch means for. selecting prearranged circuits comprising fixed contacts connected respectively to said'circuits and a shaft carrying a movable contact cooperating. with said fixed contacts, an adjustable selector switch and a selector switch in series therewith actuated by said shaft, a current source, a control relay energized from said source through said selector switches when said shaft is in position to engage said movable contact with one of said fixed contacts, means controlled by said relay to lock said shaft in a position corresponding to one of said circuits and to release said shaft upon movement of said adjustable switch to select another of said circuits, means to move said shaft longitudinally to dis engage said movable and fixedcontacts, a ratchet mechanism comprising a pawl, a spring to actuate said-pawL a magnet to retract said pawl and means controlledby said relay to energize said magnet periodically whereby saidshaft is rotated until-said relay is energizedthrough said selector switches, means to prevent overrunning of said shaft during rotation thereof and to lock said shaft against rotation by said spring while said relay is in energized condition comprising a 5. In a switching apparatus including switch 10 means for selecting prearranged circuits comprising fixed contacts connected respectively to said circuits and a shaft carrying a movable contact cooperating with said fixed contacts, an adjustable selector switch and a selector switch in 15 series therewith actuated by said shaft, a current source, a control relay energized from said source through said selector switches when said shaft is in position to engage said movable contact with one of said fixed contacts, means controlled by said relay to lock said shaft in a position corresponding to one of said circuits and to release said shaft upon movement of said adjustable switch to select another of said circuits, means to move said shaft longitudinally to disengage said movable and fixed contacts, means to rotate said shaft to a position corresponding to another of said circuits including a ratchet wheel connected to said shaft, a pawl, a spring to move said pawl into engagement with said wheel, a magnet to retract said pawl, and means controlled by said relay to energize said magnet periodically comprising a relay having slow opening contacts in series with said magnet, and a translator magnet controlled by said first relay to return said shaft to locked position.

MARWIN R. JOHNSON. 

